package

java.util.concurrent

Classes | Description

Utility classes commonly useful in concurrent programming. more...

Interfaces

BlockingQueue<E> A Queue that additionally supports operations that wait for the queue to become non-empty when retrieving an element, and wait for space to become available in the queue when storing an element. 
Callable<V> A task that returns a result and may throw an exception. 
CompletionService<V> A service that decouples the production of new asynchronous tasks from the consumption of the results of completed tasks. 
ConcurrentMap<K, V> A Map providing additional atomic putIfAbsent, remove, and replace methods. 
Delayed A mix-in style interface for marking objects that should be acted upon after a given delay. 
Executor An object that executes submitted Runnable tasks. 
ExecutorService An Executor that provides methods to manage termination and methods that can produce a Future for tracking progress of one or more asynchronous tasks. 
Future<V> A Future represents the result of an asynchronous computation. 
RejectedExecutionHandler A handler for tasks that cannot be executed by a ThreadPoolExecutor. 
ScheduledExecutorService An ExecutorService that can schedule commands to run after a given delay, or to execute periodically. 
ScheduledFuture<V> A delayed result-bearing action that can be cancelled. 
ThreadFactory An object that creates new threads on demand. 

Classes

AbstractExecutorService Provides default implementation of ExecutorService execution methods. 
ArrayBlockingQueue<E> A bounded blocking queue backed by an array. 
ConcurrentHashMap<K, V> A hash table supporting full concurrency of retrievals and adjustable expected concurrency for updates. 
ConcurrentLinkedQueue<E> An unbounded thread-safe queue based on linked nodes. 
CopyOnWriteArrayList<E> Implements a ArrayList variant that is thread-safe. 
CopyOnWriteArraySet<E> A Set that uses CopyOnWriteArrayList for all of its operations. 
CountDownLatch A synchronization aid that allows one or more threads to wait until a set of operations being performed in other threads completes. 
CyclicBarrier A synchronization aid that allows a set of threads to all wait for each other to reach a common barrier point. 
DelayQueue<E extends Delayed> An unbounded blocking queue of Delayed elements, in which an element can only be taken when its delay has expired. 
Exchanger<V> A synchronization point at which two threads can exchange objects. 
ExecutorCompletionService<V> A CompletionService that uses a supplied Executor to execute tasks. 
Executors Factory and utility methods for Executor, ExecutorService, ScheduledExecutorService, ThreadFactory, and Callable classes defined in this package. 
FutureTask<V> A cancellable asynchronous computation. 
LinkedBlockingQueue<E> An optionally-bounded blocking queue based on linked nodes. 
PriorityBlockingQueue<E> An unbounded blocking queue that uses the same ordering rules as class PriorityQueue and supplies blocking retrieval operations. 
ScheduledThreadPoolExecutor A ThreadPoolExecutor that can additionally schedule commands to run after a given delay, or to execute periodically. 
Semaphore A counting semaphore. 
SynchronousQueue<E> A blocking queue in which each put must wait for a take, and vice versa. 
ThreadPoolExecutor An ExecutorService that executes each submitted task using one of possibly several pooled threads, normally configured using Executors factory methods. 
ThreadPoolExecutor.AbortPolicy A handler for rejected tasks that throws a RejectedExecutionException. 
ThreadPoolExecutor.CallerRunsPolicy A handler for rejected tasks that runs the rejected task directly in the calling thread of the execute method, unless the executor has been shut down, in which case the task is discarded. 
ThreadPoolExecutor.DiscardOldestPolicy A handler for rejected tasks that discards the oldest unhandled request and then retries execute, unless the executor is shut down, in which case the task is discarded. 
ThreadPoolExecutor.DiscardPolicy A handler for rejected tasks that silently discards the rejected task. 

Enums

TimeUnit A TimeUnit represents time durations at a given unit of granularity and provides utility methods to convert across units, and to perform timing and delay operations in these units. 

Exceptions

BrokenBarrierException Exception thrown when a thread tries to wait upon a barrier that is in a broken state, or which enters the broken state while the thread is waiting. 
CancellationException Exception indicating that the result of a value-producing task, such as a FutureTask, cannot be retrieved because the task was cancelled. 
ExecutionException Exception thrown when attempting to retrieve the result of a task that aborted by throwing an exception. 
RejectedExecutionException Exception thrown by an Executor when a task cannot be accepted for execution. 
TimeoutException Exception thrown when a blocking operation times out.